In a large number of processing industries, gaseous or volatile materials, especially volatile organic compounds, are transported along or through a system or network having incorporated therein varied components including, for example, pipe lines, valves, fittings (including flanges, seals, and threaded connections), pumps, compressors, pressure relief devices, diaphragms, hatches, sight-glasses, meters, and the like. These industries include most notably the hydrocarbon processing industries such as petroleum refineries, chemical and petrochemical plants, oil and gas production gas facilities, natural gas processing facilities, and pipeline transfer stations, but might also include other industries or facilities such as the pharmaceutical industry, wood products industry, the ceramic industry, and the like. Any of these components interconnected throughout the plant or facility are susceptible to leaks especially at a joint or juncture due to such factors as defects in the equipment or in the connecting parts, temperature variations causing an expansion and contraction of the component especially at a joint, corrosion, or mishandling by a worker. Many or most of these gaseous or volatile organic compounds utilized or produced in these industries can be potentially toxic or hazardous, and therefore it is essential to maintain a tight system so as to avoid or minimize any leaks. For example, in order to provide a tight connection at a joint or juncture, three classes of joints are in conventional use: viz., welded joints, flanged joints, and a stuffing box as at meter and valve joints. A leak at a juncture can develop at anytime with all three classes, but the latter two are more probable to be troublesome.
The organic compounds produced or used by industry fulfill a need, and therefore usage is expansive and commonplace, and include, for example, aliphatic and aromatic hydrocarbons, alcohols, aldehydes, ketones, esters, amines, etc., and are used in or for fuels, plastics, resins, adhesives, paints, coatings, solvents, pharmaceuticals, foods, etc. However, many such organic compounds are volatile and emit antigenic or noxious fumes or gases as well as hazardous fumes or gases that can cause a fire or explosion. Moreover, the plant may generate or utilize other fumes or gases such as hydrogen or ammonia, which are noxious or hazardous. Numerous precautions or safety standards have been implemented by industry to detect or identify the sources of the gaseous or volatile fumes, to control the exposure of the worker or the environment to these fumes or gases, and to prevent the ingestion or inhalation of these fumes or gases by the worker or others within the area. Many of these fumes or gases have known toxic characteristics, and can cause irritation to the skin, eyes, nose or throat, or cause headaches, drowsiness or digestive disorders, are pathological or cause damage to internal organs (e.g., liver) or can be carcinogenic. The problem may be latent, and this noxious effect can be long-term and persist several years after the exposure to the gaseous fumes.
Several detectors or analytical devices have been developed for the purpose of detecting and monitoring gaseous or volatile emissions. Such known devices typically involve electronic instrumentation such as spectroscopy, and/or use x-ray detection, gas chromatography, laser detection, mass spectrometry, or ultrasonics, and further require comparisons and calibrations against standards and controls. In another type of detector, the analyte is drawn, sucked or pump across or over a reagent reactive with the gaseous analyte, but these detectors are not isolated from the ambient air and, therefore, are not applicable or useful for detecting in situ a fugitive emission. Techniques utilizing these devices are labor intensive and require constant, usually daily, visual and audible checking by a worker who is required to observe or test each individual joint. Also, soaps, detergents, and solutions have been used to check for leaks, and dyes have been used at joints to detect for leaks, but these are of questionable reliability, but tend to be highly variable and unreliable.
This invention has, therefore, as its purpose to provide a detector which is source specific, and to the method of using same, for detecting in situ a fugitive emission from a component containing a gaseous or volatile analyte; further requires minimal or no technical training, instrumentation, operator time, or special analyses; and is convenient, transportable, rugged, and inexpensive.